Notes: When no filename
parameter is given, the OUTFILE file name is automatically
generated using the INPUT_A file name as the base name.
If a variable name is specified then that variable contains the filename.
Image Output Files normally have an extension of ".IMG " . During
the PROCESS loop the OUT variable
is written to the specified image output file. If no input
file is declared prior to the OUTFILE statement then
the image width, height and type must be specified prior to the OUTFILE
statement. Otherwise the dimensions are the same as the most recent
INFILE file.